R. W. Hegner
HEREDITY, VARIATION, AND THE APPEARANCE OF DIVERSITIES DURING THE VEGETATIVE REPRODUCTION OF ARCELLA DENTATA
Genetics 1919 4: 95–150
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Nemesio Blanco Mendiola
VARIATION AND SELECTION WITHIN CLONAL LINES OF LEMNA MINOR
Genetics 1919 4: 151–182
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Leon J. Cole and Frank J. Kelley
STUDIES ON INHERITANCE IN PIGEONS. III. DESCRIPTION AND LINKAGE RELATIONS OF TWO SEX-LINKED CHARACTERS
Genetics 1919 4: 183–203
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